This is normal for certain kinds of media. Does the page allow using right-click > Save Link As to download the MP3? If not, you can disable playing media in a stand-alone tab as a workaround; it will still play in a player embedded in a page. Here's how: (1) In a new tab, type or paste '''about:config''' in the address bar and press Enter/Return. Click the button accepting the risk. ''More info on about:config:'' [[Configuration Editor for Firefox]]. ''The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.'' (2) In the search box in the page, type or paste '''media.play-stand-alone''' and pause while the list is filtered (3) Double-click the preference (or click the toggle button at the right end of the row) to switch the value from true to false If you later need to play audio or video in a stand-alone tab, you'll need to reverse the change. A reset button will be available at the right end of the row, or you can double-click/toggle again.